1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: evregion - Operation Region support
5 *
6 * Copyright (C) 2000 - 2019, Intel Corp.
7 *
8 *****************************************************************************/
9
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acevents.h"
13 #include "acnamesp.h"
14 #include "acinterp.h"
15
16 #define _COMPONENT ACPI_EVENTS
17 ACPI_MODULE_NAME("evregion")
18
19 extern u8 acpi_gbl_default_address_spaces[];
20
21 /* Local prototypes */
22
23 static void
24 acpi_ev_orphan_ec_reg_method(struct acpi_namespace_node *ec_device_node);
25
26 static acpi_status
27 acpi_ev_reg_run(acpi_handle obj_handle,
28 u32 level, void *context, void **return_value);
29
30 /*******************************************************************************
31 *
32 * FUNCTION: acpi_ev_initialize_op_regions
33 *
34 * PARAMETERS: None
35 *
36 * RETURN: Status
37 *
38 * DESCRIPTION: Execute _REG methods for all Operation Regions that have
39 * an installed default region handler.
40 *
41 ******************************************************************************/
42
43 acpi_status acpi_ev_initialize_op_regions(void)
44 {
45 acpi_status status;
46 u32 i;
47
48 ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
49
50 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
51 if (ACPI_FAILURE(status)) {
52 return_ACPI_STATUS(status);
53 }
54
55 /* Run the _REG methods for op_regions in each default address space */
56
57 for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
58 /*
59 * Make sure the installed handler is the DEFAULT handler. If not the
60 * default, the _REG methods will have already been run (when the
61 * handler was installed)
62 */
63 if (acpi_ev_has_default_handler(acpi_gbl_root_node,
64 acpi_gbl_default_address_spaces
65 [i])) {
66 acpi_ev_execute_reg_methods(acpi_gbl_root_node,
67 acpi_gbl_default_address_spaces
68 [i], ACPI_REG_CONNECT);
69 }
70 }
71
72 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
73 return_ACPI_STATUS(status);
74 }
75
76 /*******************************************************************************
77 *
78 * FUNCTION: acpi_ev_address_space_dispatch
79 *
80 * PARAMETERS: region_obj - Internal region object
81 * field_obj - Corresponding field. Can be NULL.
82 * function - Read or Write operation
83 * region_offset - Where in the region to read or write
84 * bit_width - Field width in bits (8, 16, 32, or 64)
85 * value - Pointer to in or out value, must be
86 * a full 64-bit integer
87 *
88 * RETURN: Status
89 *
90 * DESCRIPTION: Dispatch an address space or operation region access to
91 * a previously installed handler.
92 *
93 * NOTE: During early initialization, we always install the default region
94 * handlers for Memory, I/O and PCI_Config. This ensures that these operation
95 * region address spaces are always available as per the ACPI specification.
96 * This is especially needed in order to support the execution of
97 * module-level AML code during loading of the ACPI tables.
98 *
99 ******************************************************************************/
100
101 acpi_status
102 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
103 union acpi_operand_object *field_obj,
104 u32 function,
105 u32 region_offset, u32 bit_width, u64 *value)
106 {
107 acpi_status status;
108 acpi_adr_space_handler handler;
109 acpi_adr_space_setup region_setup;
110 union acpi_operand_object *handler_desc;
111 union acpi_operand_object *region_obj2;
112 void *region_context = NULL;
113 struct acpi_connection_info *context;
114 acpi_physical_address address;
115
116 ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
117
118 region_obj2 = acpi_ns_get_secondary_object(region_obj);
119 if (!region_obj2) {
120 return_ACPI_STATUS(AE_NOT_EXIST);
121 }
122
123 /* Ensure that there is a handler associated with this region */
124
125 handler_desc = region_obj->region.handler;
126 if (!handler_desc) {
127 ACPI_ERROR((AE_INFO,
128 "No handler for Region [%4.4s] (%p) [%s]",
129 acpi_ut_get_node_name(region_obj->region.node),
130 region_obj,
131 acpi_ut_get_region_name(region_obj->region.
132 space_id)));
133
134 return_ACPI_STATUS(AE_NOT_EXIST);
135 }
136
137 context = handler_desc->address_space.context;
138
139 /*
140 * It may be the case that the region has never been initialized.
141 * Some types of regions require special init code
142 */
143 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
144
145 /* This region has not been initialized yet, do it */
146
147 region_setup = handler_desc->address_space.setup;
148 if (!region_setup) {
149
150 /* No initialization routine, exit with error */
151
152 ACPI_ERROR((AE_INFO,
153 "No init routine for region(%p) [%s]",
154 region_obj,
155 acpi_ut_get_region_name(region_obj->region.
156 space_id)));
157 return_ACPI_STATUS(AE_NOT_EXIST);
158 }
159
160 /*
161 * We must exit the interpreter because the region setup will
162 * potentially execute control methods (for example, the _REG method
163 * for this region)
164 */
165 acpi_ex_exit_interpreter();
166
167 status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
168 context, ®ion_context);
169
170 /* Re-enter the interpreter */
171
172 acpi_ex_enter_interpreter();
173
174 /* Check for failure of the Region Setup */
175
176 if (ACPI_FAILURE(status)) {
177 ACPI_EXCEPTION((AE_INFO, status,
178 "During region initialization: [%s]",
179 acpi_ut_get_region_name(region_obj->
180 region.
181 space_id)));
182 return_ACPI_STATUS(status);
183 }
184
185 /* Region initialization may have been completed by region_setup */
186
187 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
188 region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
189
190 /*
191 * Save the returned context for use in all accesses to
192 * the handler for this particular region
193 */
194 if (!(region_obj2->extra.region_context)) {
195 region_obj2->extra.region_context =
196 region_context;
197 }
198 }
199 }
200
201 /* We have everything we need, we can invoke the address space handler */
202
203 handler = handler_desc->address_space.handler;
204 address = (region_obj->region.address + region_offset);
205
206 /*
207 * Special handling for generic_serial_bus and general_purpose_io:
208 * There are three extra parameters that must be passed to the
209 * handler via the context:
210 * 1) Connection buffer, a resource template from Connection() op
211 * 2) Length of the above buffer
212 * 3) Actual access length from the access_as() op
213 *
214 * In addition, for general_purpose_io, the Address and bit_width fields
215 * are defined as follows:
216 * 1) Address is the pin number index of the field (bit offset from
217 * the previous Connection)
218 * 2) bit_width is the actual bit length of the field (number of pins)
219 */
220 if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS) &&
221 context && field_obj) {
222
223 /* Get the Connection (resource_template) buffer */
224
225 context->connection = field_obj->field.resource_buffer;
226 context->length = field_obj->field.resource_length;
227 context->access_length = field_obj->field.access_length;
228 }
229 if ((region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
230 context && field_obj) {
231
232 /* Get the Connection (resource_template) buffer */
233
234 context->connection = field_obj->field.resource_buffer;
235 context->length = field_obj->field.resource_length;
236 context->access_length = field_obj->field.access_length;
237 address = field_obj->field.pin_number_index;
238 bit_width = field_obj->field.bit_length;
239 }
240
241 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
242 "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
243 ®ion_obj->region.handler->address_space, handler,
244 ACPI_FORMAT_UINT64(address),
245 acpi_ut_get_region_name(region_obj->region.
246 space_id)));
247
248 if (!(handler_desc->address_space.handler_flags &
249 ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
250 /*
251 * For handlers other than the default (supplied) handlers, we must
252 * exit the interpreter because the handler *might* block -- we don't
253 * know what it will do, so we can't hold the lock on the interpreter.
254 */
255 acpi_ex_exit_interpreter();
256 }
257
258 /* Call the handler */
259
260 status = handler(function, address, bit_width, value, context,
261 region_obj2->extra.region_context);
262
263 if (ACPI_FAILURE(status)) {
264 ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
265 acpi_ut_get_region_name(region_obj->region.
266 space_id)));
267
268 /*
269 * Special case for an EC timeout. These are seen so frequently
270 * that an additional error message is helpful
271 */
272 if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
273 (status == AE_TIME)) {
274 ACPI_ERROR((AE_INFO,
275 "Timeout from EC hardware or EC device driver"));
276 }
277 }
278
279 if (!(handler_desc->address_space.handler_flags &
280 ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
281 /*
282 * We just returned from a non-default handler, we must re-enter the
283 * interpreter
284 */
285 acpi_ex_enter_interpreter();
286 }
287
288 return_ACPI_STATUS(status);
289 }
290
291 /*******************************************************************************
292 *
293 * FUNCTION: acpi_ev_detach_region
294 *
295 * PARAMETERS: region_obj - Region Object
296 * acpi_ns_is_locked - Namespace Region Already Locked?
297 *
298 * RETURN: None
299 *
300 * DESCRIPTION: Break the association between the handler and the region
301 * this is a two way association.
302 *
303 ******************************************************************************/
304
305 void
306 acpi_ev_detach_region(union acpi_operand_object *region_obj,
307 u8 acpi_ns_is_locked)
308 {
309 union acpi_operand_object *handler_obj;
310 union acpi_operand_object *obj_desc;
311 union acpi_operand_object *start_desc;
312 union acpi_operand_object **last_obj_ptr;
313 acpi_adr_space_setup region_setup;
314 void **region_context;
315 union acpi_operand_object *region_obj2;
316 acpi_status status;
317
318 ACPI_FUNCTION_TRACE(ev_detach_region);
319
320 region_obj2 = acpi_ns_get_secondary_object(region_obj);
321 if (!region_obj2) {
322 return_VOID;
323 }
324 region_context = ®ion_obj2->extra.region_context;
325
326 /* Get the address handler from the region object */
327
328 handler_obj = region_obj->region.handler;
329 if (!handler_obj) {
330
331 /* This region has no handler, all done */
332
333 return_VOID;
334 }
335
336 /* Find this region in the handler's list */
337
338 obj_desc = handler_obj->address_space.region_list;
339 start_desc = obj_desc;
340 last_obj_ptr = &handler_obj->address_space.region_list;
341
342 while (obj_desc) {
343
344 /* Is this the correct Region? */
345
346 if (obj_desc == region_obj) {
347 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
348 "Removing Region %p from address handler %p\n",
349 region_obj, handler_obj));
350
351 /* This is it, remove it from the handler's list */
352
353 *last_obj_ptr = obj_desc->region.next;
354 obj_desc->region.next = NULL; /* Must clear field */
355
356 if (acpi_ns_is_locked) {
357 status =
358 acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
359 if (ACPI_FAILURE(status)) {
360 return_VOID;
361 }
362 }
363
364 /* Now stop region accesses by executing the _REG method */
365
366 status =
367 acpi_ev_execute_reg_method(region_obj,
368 ACPI_REG_DISCONNECT);
369 if (ACPI_FAILURE(status)) {
370 ACPI_EXCEPTION((AE_INFO, status,
371 "from region _REG, [%s]",
372 acpi_ut_get_region_name
373 (region_obj->region.space_id)));
374 }
375
376 if (acpi_ns_is_locked) {
377 status =
378 acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
379 if (ACPI_FAILURE(status)) {
380 return_VOID;
381 }
382 }
383
384 /*
385 * If the region has been activated, call the setup handler with
386 * the deactivate notification
387 */
388 if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
389 region_setup = handler_obj->address_space.setup;
390 status =
391 region_setup(region_obj,
392 ACPI_REGION_DEACTIVATE,
393 handler_obj->address_space.
394 context, region_context);
395
396 /*
397 * region_context should have been released by the deactivate
398 * operation. We don't need access to it anymore here.
399 */
400 if (region_context) {
401 *region_context = NULL;
402 }
403
404 /* Init routine may fail, Just ignore errors */
405
406 if (ACPI_FAILURE(status)) {
407 ACPI_EXCEPTION((AE_INFO, status,
408 "from region handler - deactivate, [%s]",
409 acpi_ut_get_region_name
410 (region_obj->region.
411 space_id)));
412 }
413
414 region_obj->region.flags &=
415 ~(AOPOBJ_SETUP_COMPLETE);
416 }
417
418 /*
419 * Remove handler reference in the region
420 *
421 * NOTE: this doesn't mean that the region goes away, the region
422 * is just inaccessible as indicated to the _REG method
423 *
424 * If the region is on the handler's list, this must be the
425 * region's handler
426 */
427 region_obj->region.handler = NULL;
428 acpi_ut_remove_reference(handler_obj);
429
430 return_VOID;
431 }
432
433 /* Walk the linked list of handlers */
434
435 last_obj_ptr = &obj_desc->region.next;
436 obj_desc = obj_desc->region.next;
437
438 /* Prevent infinite loop if list is corrupted */
439
440 if (obj_desc == start_desc) {
441 ACPI_ERROR((AE_INFO,
442 "Circular handler list in region object %p",
443 region_obj));
444 return_VOID;
445 }
446 }
447
448 /* If we get here, the region was not in the handler's region list */
449
450 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
451 "Cannot remove region %p from address handler %p\n",
452 region_obj, handler_obj));
453
454 return_VOID;
455 }
456
457 /*******************************************************************************
458 *
459 * FUNCTION: acpi_ev_attach_region
460 *
461 * PARAMETERS: handler_obj - Handler Object
462 * region_obj - Region Object
463 * acpi_ns_is_locked - Namespace Region Already Locked?
464 *
465 * RETURN: None
466 *
467 * DESCRIPTION: Create the association between the handler and the region
468 * this is a two way association.
469 *
470 ******************************************************************************/
471
472 acpi_status
473 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
474 union acpi_operand_object *region_obj,
475 u8 acpi_ns_is_locked)
476 {
477
478 ACPI_FUNCTION_TRACE(ev_attach_region);
479
480 /* Install the region's handler */
481
482 if (region_obj->region.handler) {
483 return_ACPI_STATUS(AE_ALREADY_EXISTS);
484 }
485
486 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
487 "Adding Region [%4.4s] %p to address handler %p [%s]\n",
488 acpi_ut_get_node_name(region_obj->region.node),
489 region_obj, handler_obj,
490 acpi_ut_get_region_name(region_obj->region.
491 space_id)));
492
493 /* Link this region to the front of the handler's list */
494
495 region_obj->region.next = handler_obj->address_space.region_list;
496 handler_obj->address_space.region_list = region_obj;
497 region_obj->region.handler = handler_obj;
498 acpi_ut_add_reference(handler_obj);
499
500 return_ACPI_STATUS(AE_OK);
501 }
502
503 /*******************************************************************************
504 *
505 * FUNCTION: acpi_ev_execute_reg_method
506 *
507 * PARAMETERS: region_obj - Region object
508 * function - Passed to _REG: On (1) or Off (0)
509 *
510 * RETURN: Status
511 *
512 * DESCRIPTION: Execute _REG method for a region
513 *
514 ******************************************************************************/
515
516 acpi_status
517 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
518 {
519 struct acpi_evaluate_info *info;
520 union acpi_operand_object *args[3];
521 union acpi_operand_object *region_obj2;
522 const acpi_name *reg_name_ptr =
523 ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
524 struct acpi_namespace_node *method_node;
525 struct acpi_namespace_node *node;
526 acpi_status status;
527
528 ACPI_FUNCTION_TRACE(ev_execute_reg_method);
529
530 if (!acpi_gbl_namespace_initialized ||
531 region_obj->region.handler == NULL) {
532 return_ACPI_STATUS(AE_OK);
533 }
534
535 region_obj2 = acpi_ns_get_secondary_object(region_obj);
536 if (!region_obj2) {
537 return_ACPI_STATUS(AE_NOT_EXIST);
538 }
539
540 /*
541 * Find any "_REG" method associated with this region definition.
542 * The method should always be updated as this function may be
543 * invoked after a namespace change.
544 */
545 node = region_obj->region.node->parent;
546 status =
547 acpi_ns_search_one_scope(*reg_name_ptr, node, ACPI_TYPE_METHOD,
548 &method_node);
549 if (ACPI_SUCCESS(status)) {
550 /*
551 * The _REG method is optional and there can be only one per
552 * region definition. This will be executed when the handler is
553 * attached or removed.
554 */
555 region_obj2->extra.method_REG = method_node;
556 }
557 if (region_obj2->extra.method_REG == NULL) {
558 return_ACPI_STATUS(AE_OK);
559 }
560
561 /* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
562
563 if ((function == ACPI_REG_CONNECT &&
564 region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
565 (function == ACPI_REG_DISCONNECT &&
566 !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
567 return_ACPI_STATUS(AE_OK);
568 }
569
570 /* Allocate and initialize the evaluation information block */
571
572 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
573 if (!info) {
574 return_ACPI_STATUS(AE_NO_MEMORY);
575 }
576
577 info->prefix_node = region_obj2->extra.method_REG;
578 info->relative_pathname = NULL;
579 info->parameters = args;
580 info->flags = ACPI_IGNORE_RETURN_VALUE;
581
582 /*
583 * The _REG method has two arguments:
584 *
585 * arg0 - Integer:
586 * Operation region space ID Same value as region_obj->Region.space_id
587 *
588 * arg1 - Integer:
589 * connection status 1 for connecting the handler, 0 for disconnecting
590 * the handler (Passed as a parameter)
591 */
592 args[0] =
593 acpi_ut_create_integer_object((u64)region_obj->region.space_id);
594 if (!args[0]) {
595 status = AE_NO_MEMORY;
596 goto cleanup1;
597 }
598
599 args[1] = acpi_ut_create_integer_object((u64)function);
600 if (!args[1]) {
601 status = AE_NO_MEMORY;
602 goto cleanup2;
603 }
604
605 args[2] = NULL; /* Terminate list */
606
607 /* Execute the method, no return value */
608
609 ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
610 (ACPI_TYPE_METHOD, info->prefix_node, NULL));
611
612 status = acpi_ns_evaluate(info);
613 acpi_ut_remove_reference(args[1]);
614
615 if (ACPI_FAILURE(status)) {
616 goto cleanup2;
617 }
618
619 if (function == ACPI_REG_CONNECT) {
620 region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
621 } else {
622 region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
623 }
624
625 cleanup2:
626 acpi_ut_remove_reference(args[0]);
627
628 cleanup1:
629 ACPI_FREE(info);
630 return_ACPI_STATUS(status);
631 }
632
633 /*******************************************************************************
634 *
635 * FUNCTION: acpi_ev_execute_reg_methods
636 *
637 * PARAMETERS: node - Namespace node for the device
638 * space_id - The address space ID
639 * function - Passed to _REG: On (1) or Off (0)
640 *
641 * RETURN: None
642 *
643 * DESCRIPTION: Run all _REG methods for the input Space ID;
644 * Note: assumes namespace is locked, or system init time.
645 *
646 ******************************************************************************/
647
648 void
649 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
650 acpi_adr_space_type space_id, u32 function)
651 {
652 struct acpi_reg_walk_info info;
653
654 ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
655
656 /*
657 * These address spaces do not need a call to _REG, since the ACPI
658 * specification defines them as: "must always be accessible". Since
659 * they never change state (never become unavailable), no need to ever
660 * call _REG on them. Also, a data_table is not a "real" address space,
661 * so do not call _REG. September 2018.
662 */
663 if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
664 (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
665 (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
666 return_VOID;
667 }
668
669 info.space_id = space_id;
670 info.function = function;
671 info.reg_run_count = 0;
672
673 ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
674 " Running _REG methods for SpaceId %s\n",
675 acpi_ut_get_region_name(info.space_id)));
676
677 /*
678 * Run all _REG methods for all Operation Regions for this space ID. This
679 * is a separate walk in order to handle any interdependencies between
680 * regions and _REG methods. (i.e. handlers must be installed for all
681 * regions of this Space ID before we can run any _REG methods)
682 */
683 (void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
684 ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, NULL,
685 &info, NULL);
686
687 /* Special case for EC: handle "orphan" _REG methods with no region */
688
689 if (space_id == ACPI_ADR_SPACE_EC) {
690 acpi_ev_orphan_ec_reg_method(node);
691 }
692
693 ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
694 " Executed %u _REG methods for SpaceId %s\n",
695 info.reg_run_count,
696 acpi_ut_get_region_name(info.space_id)));
697
698 return_VOID;
699 }
700
701 /*******************************************************************************
702 *
703 * FUNCTION: acpi_ev_reg_run
704 *
705 * PARAMETERS: walk_namespace callback
706 *
707 * DESCRIPTION: Run _REG method for region objects of the requested spaceID
708 *
709 ******************************************************************************/
710
711 static acpi_status
712 acpi_ev_reg_run(acpi_handle obj_handle,
713 u32 level, void *context, void **return_value)
714 {
715 union acpi_operand_object *obj_desc;
716 struct acpi_namespace_node *node;
717 acpi_status status;
718 struct acpi_reg_walk_info *info;
719
720 info = ACPI_CAST_PTR(struct acpi_reg_walk_info, context);
721
722 /* Convert and validate the device handle */
723
724 node = acpi_ns_validate_handle(obj_handle);
725 if (!node) {
726 return (AE_BAD_PARAMETER);
727 }
728
729 /*
730 * We only care about regions and objects that are allowed to have
731 * address space handlers
732 */
733 if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
734 return (AE_OK);
735 }
736
737 /* Check for an existing internal object */
738
739 obj_desc = acpi_ns_get_attached_object(node);
740 if (!obj_desc) {
741
742 /* No object, just exit */
743
744 return (AE_OK);
745 }
746
747 /* Object is a Region */
748
749 if (obj_desc->region.space_id != info->space_id) {
750
751 /* This region is for a different address space, just ignore it */
752
753 return (AE_OK);
754 }
755
756 info->reg_run_count++;
757 status = acpi_ev_execute_reg_method(obj_desc, info->function);
758 return (status);
759 }
760
761 /*******************************************************************************
762 *
763 * FUNCTION: acpi_ev_orphan_ec_reg_method
764 *
765 * PARAMETERS: ec_device_node - Namespace node for an EC device
766 *
767 * RETURN: None
768 *
769 * DESCRIPTION: Execute an "orphan" _REG method that appears under the EC
770 * device. This is a _REG method that has no corresponding region
771 * within the EC device scope. The orphan _REG method appears to
772 * have been enabled by the description of the ECDT in the ACPI
773 * specification: "The availability of the region space can be
774 * detected by providing a _REG method object underneath the
775 * Embedded Controller device."
776 *
777 * To quickly access the EC device, we use the ec_device_node used
778 * during EC handler installation. Otherwise, we would need to
779 * perform a time consuming namespace walk, executing _HID
780 * methods to find the EC device.
781 *
782 * MUTEX: Assumes the namespace is locked
783 *
784 ******************************************************************************/
785
786 static void
787 acpi_ev_orphan_ec_reg_method(struct acpi_namespace_node *ec_device_node)
788 {
789 acpi_handle reg_method;
790 struct acpi_namespace_node *next_node;
791 acpi_status status;
792 struct acpi_object_list args;
793 union acpi_object objects[2];
794
795 ACPI_FUNCTION_TRACE(ev_orphan_ec_reg_method);
796
797 if (!ec_device_node) {
798 return_VOID;
799 }
800
801 /* Namespace is currently locked, must release */
802
803 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
804
805 /* Get a handle to a _REG method immediately under the EC device */
806
807 status = acpi_get_handle(ec_device_node, METHOD_NAME__REG, ®_method);
808 if (ACPI_FAILURE(status)) {
809 goto exit; /* There is no _REG method present */
810 }
811
812 /*
813 * Execute the _REG method only if there is no Operation Region in
814 * this scope with the Embedded Controller space ID. Otherwise, it
815 * will already have been executed. Note, this allows for Regions
816 * with other space IDs to be present; but the code below will then
817 * execute the _REG method with the embedded_control space_ID argument.
818 */
819 next_node = acpi_ns_get_next_node(ec_device_node, NULL);
820 while (next_node) {
821 if ((next_node->type == ACPI_TYPE_REGION) &&
822 (next_node->object) &&
823 (next_node->object->region.space_id == ACPI_ADR_SPACE_EC)) {
824 goto exit; /* Do not execute the _REG */
825 }
826
827 next_node = acpi_ns_get_next_node(ec_device_node, next_node);
828 }
829
830 /* Evaluate the _REG(embedded_control,Connect) method */
831
832 args.count = 2;
833 args.pointer = objects;
834 objects[0].type = ACPI_TYPE_INTEGER;
835 objects[0].integer.value = ACPI_ADR_SPACE_EC;
836 objects[1].type = ACPI_TYPE_INTEGER;
837 objects[1].integer.value = ACPI_REG_CONNECT;
838
839 status = acpi_evaluate_object(reg_method, NULL, &args, NULL);
840
841 exit:
842 /* We ignore all errors from above, don't care */
843
844 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
845 return_VOID;
846 }